Power-assisted gurneys capable of transporting a patient from either the scene of an accident or from one facility to another facility, are described in U.S. Pat. Nos. 5,495,914, 5,697,471, 5,740,884, 5,887,302 and 5,983,425, all including as a co-inventor the inventor of this disclosure. Each of these patents is hereby incorporated by reference in its entirely. These patents describe various techniques for allowing the power lifting unit to raise or lower the transporter and also describe electronic controls which allow a single operator to operate the transporter. In addition, U.S. Pat. No. 5,983,425 discloses a structure which allows an electric motor to be engaged to assist in raising or lowering the transporter and disengaged to allow the transporter to be raised or lowered manually. U.S. Pat. No. 5,887,302 describes a circuit for controlling an electric motor used to raise or lower the gurney as well as to provide a jog pulse to the electric motor.
A continuing problem associated with battery-operated raisable or lowerable gurneys is the requirement that the battery associated with the drive motor used to raise or lower the gurney have both a long life and be light weight. These two requirements conflict. Thus, there is a need for a more efficient, lighter structure for raising and lowering a battery-powered gurney to extend battery life and to lower the weight of the total gurney.